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    <title>Document</title>
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<script>
    var a = 10;
    //       a   11    12     13     12     11
    // var sum = a++ + ++a + ++a*2 + a-- + --a;
    //     sum = 10  + 12  + 13*2  + 13  +  11
    //         = 10  + 12 +  26 + 24
    //         = 72 

    console.log(a,sum);



</script>
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